In previous work on enhancing the energy efficiency of radio networks, solutions have been considered for energy savings on a Radio base station (RBS) level. For example, a radio base station may operate in a low power mode during low data traffic hours. An area of equal importance that has obtained less attention is the dimensioning of the power backup system, and in the power supply system of a radio site comprising radio base stations. The power supply system of a radio base station may comprise the main electrical network but may also comprise a typical off grid site solution of different energy sources, such as solar, wind, diesel, water and/or the like.
Today's radio base station products ways to limit the energy consumption are limited. There are features proposed to reduce the power consumption based on the current data traffic load, but the operation of the radio base station is directed to save power consumption decreasing the operating expenditures.